A short comment on Morse Code in the Ameliapedia."Morse code key questions"Abandonment of CW (Morse Code)":Earhart and Noonan were ahead of their time in asking that the Itasca communicate with them solely via voice transmissions. That is now the worldwide norm for aircraft. In 1937, the worldwide norm was Morse code transmitted on continuous wave (CW) or modified continuous wave (MCW). The Itasca
could not transmit voice on all frequencies (e.g., 7500 kHz)."As the result of a talk with Mr. E. Chater and Mr. Balfour the Lae radio operator it is very apparent that the weak link in the combination was the crew’s lack of expert knowledge of radio. Their morse was very slow and they preferred to use telephony as much as possible"
("Collopy Letter")."On enquiry Miss Earhart and Captain Noonan advised that they entirely depended on radio telephone reception as neither of them were able to read morse at any speed but could recognise an individual letter sent several times. This point was again mentioned by both of them later when two different sets at Lae were used for listening in for time signals"
("Chater Report")."Miss Earhart and Captain Noonan spent a considerable time in the radio office and as previously mentioned it was learned that neither of them could read morse at any speed but could only distinguish letters made individually slowly and repeated often; in that case their direction finding apparatus would be useless or misleading unless they were taking a bearing on a station using radiophone which could give the station position on voice. We understand the Itasca was to do this but if the plane was unable to pick up the Itasca it is doubtful if the direction finder would be any use to her"
("Chater Report").